The reproducing earthquakes of the Galapagos Islands

1980 ◽  
Vol 70 (5) ◽  
pp. 1759-1770
Author(s):  
Kris Kaufman ◽  
L. J. Burdick

abstract The largest swarm of earthquakes of the last few decades accompanied the collapse of the Fernandina caldera in the Galapagos Islands in June of 1968. Many of the events were relatively large. (The largest 21 had moments ranging from 6 ×1024 to 12 ×1024 dyne-cm.) They produced teleseismic WWSSN records that were spectacularly consistent from event to event. The entire wave trains of the signals were nearly identical on any given component at any given station. This indicates that the mode of strain release in the region was unusually stable and coherent. The body waveforms of the events have been modeled with synthetic seismograms. The best fault plane solution was found to be: strike = 335°, dip = 47°, and rake = 247°. The depths of all the larger shocks were close to 14 km. Previous work had suggested that the seismic energy was radiated by the collapsing caldera block at a depth of about 1 km. The new results indicate that large scale extensional faulting at depth was an important part of the multifaceted event during which the caldera collapsed.

2013 ◽  
Vol 33 ◽  
pp. 3-12 ◽  
Author(s):  
C. Collins ◽  
A. Mascarenhas ◽  
R. Martinez

Abstract. From 27 March to 5 April 2009, upper ocean velocities between the Galápagos Islands and Ecuador were measured using a vessel mounted ADCP. A region of possible strong cross-hemisphere exchange was observed immediately to the east of the Galápagos, where a shallow (200 m) 300 km wide northeastward surface flow transported 7–11 Sv. Underlying this strong northeastward surface current, a southward flowing undercurrent was observed which was at least 600 m thick, 100 km wide, and had an observed transport of 7–8 Sv. Next to the Ecuador coast, the shallow (< 200 m) Ecuador Coastal Current was observed to extend offshore 100 km with strongest flow, 0.33 m s−1, near the surface. Immediately to the west of the Ecuador Coastal Current, flow was directed eastward and southward into the beginnings of the Peru-Chile Countercurrent. The integral of the surface currents between the Galápagos and Ecuador agreed well with observed sea level differences. Although the correlation of the sea level differences with large scale climate indices (Niño3 and the Southern Oscillation Index) was significant, more than half of the sea level variability was not explained. Seasonal variability of the sea level difference indicated that sea level was 2 cm higher at the Galápagos during late winter and early spring, which could be associated with the pattern of northward surface flows observed by R/V Knorr.


Marine plankton flagellates attributable to Michaelsarsia elegans Gran (type species of its genus) and Halopappus adriaticus Schiller (sensu Gaarder) have been investigated by means of scanning and transmission electron microscopy supplementing light microscopy of dry whole mounts prepared in situ in the Galapagos Islands. Some external features, notably coccolith arrangement, have been re-interpreted, and information on others added or amplified. Some of the new details include the body coccoliths, which have been shown to be more complex than previously supposed, the bar-crystallites in particular being compound in both taxa. In addition, unmineralized components are shown to be present in all types of coccolith. They include patternless membranes spread across the proximal faces of body coccoliths and occupying the apparently vacant centres of ring-shaped coccoliths, while a highly characteristic, fragile, reticulum is limited to the central areas of the elongated appendage links in both taxa. The impact of these findings on general biological concepts is discussed in a preliminary way, drawing on cognate data previously published for Ophiaster and Calciopappus . It is concluded that the presence of apical appendages (anterior or posterior) in each of these genera is an independently acquired adaptation to some as yet unknown environmental factor or factors, whereas coccolith substructure is phyletically more meaningful. This indicates that Michael-sarsia , to which H. adriaticus should be transferred, is more remote from the other two genera than has hitherto been supposed. Finally an attempt has been made, in the light of aff the evidence, to assess for the first time the possible functional significance of the unmineralized coccolith components and some constructive suggestions have been tentatively formulated. The paper ends with a factual summary in the form of revised taxonomic diagnoses for M. elegans , M. adriaticus and the genus Michaelsarsia .


Author(s):  
Deborah Carr ◽  
Vera K. Tsenkova

The body weight of U.S. adults and children has risen markedly over the past three decades. The physical health consequences of obesity are widely documented, and emerging research from the Midlife in the United States study and other large-scale surveys reveals the harmful impact of obesity on adults’ psychosocial and interpersonal well-being. This chapter synthesizes recent research on the psychosocial implications of body weight, with attention to explanatory mechanisms and subgroup differences in these patterns. A brief statistical portrait of body weight is provided, documenting rates and correlates of obesity, with a focus on race, gender, and socioeconomic status disparities. The consequences of body weight for three main outcomes are described: institutional and everyday discrimination, interpersonal relationships, and psychological well-being. The chapter concludes with a discussion of the ways that recent integrative health research on the psychosocial consequences of overweight and obesity inform our understanding of population health.


2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Daniel Escobar-Camacho ◽  
Paulina Rosero ◽  
Mauricio Castrejón ◽  
Carlos F. Mena ◽  
Francisco Cuesta

AbstractThe unique marine and terrestrial ecosystems of the Galapagos Islands are highly vulnerable to human-based drivers of change, including the introduction of invasive species, unsustainable tourism, illegal fishing, overexploitation of ecosystem services, and climate change. These drivers can interact with climate-based drivers such as El Niño-Southern Oscillation (ENSO) at multiple temporal and spatial scales, exacerbating their negative impacts on already fragile ecosystems and the socioeconomic system of the Archipelago. In this review, we performed a literature review based on published literature from 1945 to 2020 and local and global climate databases to analyze drivers of change in the Galapagos. We developed and applied a spatial impact assessment model to identify high-ecological value areas with high sensitivity and exposure scores to environmental change drivers. We identified 13 priority HEVA that encompass ca. 23% (14,715 km2) of the Galapagos Archipelago, distributed in nearly 3% of the Galapagos Marine Reserve and 20% Galapagos National Park. Current and future impacts are likely to concentrate on the inhabited islands’ highlands, whereas marine impacts concentrate along most of the Galapagos Islands’ shorelines. These results are important for guiding the design and implementation of adaptation measures aimed at increasing ecosystem resilience and human adaptive capacity in the face of global environmental change. Overall, these results will be valuable in their application for preserving Galapagos biota, securing the provision of vital ecosystem services for resident human populations, and sustaining the nature-based tourism industry.


2021 ◽  
pp. 100180
Author(s):  
William F. Vásquez ◽  
Nejem Raheem ◽  
Diego Quiroga ◽  
Valeria Ochoa-Herrera

2011 ◽  
Vol 65 (4) ◽  
pp. 507-513 ◽  
Author(s):  
Mark S. Hoddle ◽  
Laurence A. Mound

Author(s):  
Polpass Arul Jose ◽  
Michael Ben‐Yosef ◽  
Paola Lahuatte ◽  
Charlotte E. Causton ◽  
George E. Heimpel ◽  
...  

Author(s):  
A. Cano ◽  
Paul Arévalo ◽  
F. Jurado

This research compared different sizing methods to improve the current autonomous hybrid system in the Galapagos Islands in 2031, analyzing the loss of power supply probability (LPSP).


Radiocarbon ◽  
1993 ◽  
Vol 35 (2) ◽  
pp. 245-251 ◽  
Author(s):  
T. A. Brown ◽  
G. W. Farwell ◽  
P. M. Grootes ◽  
F. H. Schmidt ◽  
Minze Stuiver

We report AMS 14C measurements on subannual samples of coral from the Galapagos Islands that span the period, 1970–1973. Both the major 1972 El Niño/Southern Oscillation event and intra-annual changes in regional upwelling of 14C-depleted waters associated with alternation of surface-ocean current patterns are evident in the record. Our data show that the corals preserve a detailed record of past intra-annual variations of the 14C content of surface ocean water.


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